The activities of the multilateral development banks (MDBs) can have adverse impacts on water resources in an array of situations. It is obvious as regard their support to development projects related to agricultural or hydroelectric development, or to drinking water and sanitation infrastructure projects, but virtually all sectors of development can also result in water pollution or a reduction in access to water: mining, transportation, forestry, energy (other than hydroelectricity), housing… It is thus crucially important to ensure that people have the means to make themselves heard when harm to water resources occurs as collateral damage. In this contribution, access to justice is seen as a component of public participation. It allows public participation during the full lifecycle of norms, not only at the stage of decision- and law-making but taking account of their implementation and compliance-monitoring, possibly resulting in modifying the content of norms and/or procedures at issue.